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1.
Nat Commun ; 12(1): 2089, 2021 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-33828081

RESUMEN

Increasing global temperatures are predicted to stimulate soil microbial respiration. The direct and indirect impacts of warming on soil microbes, nevertheless, remain unclear. This is particularly true for understudied subsoil microbes. Here, we show that 4.5 years of whole-profile soil warming in a temperate mixed forest results in altered microbial community composition and metabolism in surface soils, partly due to carbon limitation. However, microbial communities in the subsoil responded differently to warming than in the surface. Throughout the soil profile-but to a greater extent in the subsoil-physiologic and genomic measurements show that phylogenetically different microbes could utilize complex organic compounds, dampening the effect of altered resource availability induced by warming. We find subsoil microbes had 20% lower carbon use efficiencies and 47% lower growth rates compared to surface soils, which constrain microbial communities. Collectively, our results show that unlike in surface soils, elevated microbial respiration in subsoils may continue without microbial community change in the near-term.


Asunto(s)
Calentamiento Global , Metagenoma , Microbiología del Suelo , Suelo/química , Bacterias/clasificación , Bacterias/genética , California , Carbono/metabolismo , Bosques , Microbiota , Nitrógeno/metabolismo , ARN Ribosómico 16S , Temperatura
3.
Nature ; 592(7852): 8, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33790451
4.
J Insect Sci ; 21(2)2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33844017

RESUMEN

The codling moth Cydia pomonella (L.) (Lepidoptera: Tortricidae) is a destructive pest of apple (Malus domestica (Rosales: Rosaceae)), pear (Pyrus spp. (Rosales: Rosaceae)), and other pome tree fruits; outbreaks cause significant ecological and economic losses. In this study, we used CLIMEX model to predict and evaluate the global risk of C. pomonella based on historical climate data (1989-2018) and simulated future climate data (2071-2100) under the RCP4.5 scenarios. Cydia pomonella exhibited a wide distribution under both historical and future climate conditions. Climate change is predicted to expand the northern boundary of the potential distribution from approximately 60°N to 75°N. Temperature was the most dominant factor in climatic suitability for the pest. Combinations of multiple meteorological factors (relative humidity and precipitation) associated with a failure to break diapause in certain regions also affect suitability, particularly in northern South America and central Africa. Irrigation only had a slight impact on species favorability in some areas. The projections established in our study present insight into the global potential suitability of C. pomonella under climate change scenarios by the end of the 21st century. Farmers should be aware of the risk associated with the pest based on the results, which would provide guidance for quarantine agencies and trade negotiators worldwide.


Asunto(s)
Cambio Climático , Modelos Estadísticos , Mariposas Nocturnas , Dinámica Poblacional , Animales , Clima , Productos Agrícolas/economía , Diapausa , Análisis Factorial , Frutas , Calentamiento Global , Malus , Mariposas Nocturnas/crecimiento & desarrollo , Mariposas Nocturnas/fisiología , Control de Plagas , Pyrus , Temperatura , Árboles
6.
Nat Commun ; 12(1): 2214, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33850157

RESUMEN

Forecasting which species/ecosystems are most vulnerable to climate warming is essential to guide conservation strategies to minimize extinction. Tropical/mid-latitude species are predicted to be most at risk as they live close to their upper critical thermal limits (CTLs). However, these assessments assume that upper CTL estimates, such as CTmax, are accurate predictors of vulnerability and ignore the potential for evolution to ameliorate temperature increases. Here, we use experimental evolution to assess extinction risk and adaptation in tropical and widespread Drosophila species. We find tropical species succumb to extinction before widespread species. Male fertility thermal limits, which are much lower than CTmax, are better predictors of species' current distributions and extinction in the laboratory. We find little evidence of adaptive responses to warming in any species. These results suggest that species are living closer to their upper thermal limits than currently presumed and evolution/plasticity are unlikely to rescue populations from extinction.


Asunto(s)
Cambio Climático , Fertilidad/fisiología , Calentamiento Global , Calor , Adaptación Fisiológica , Animales , Drosophila/fisiología , Ecosistema , Femenino , Masculino , Temperatura , Termotolerancia/fisiología , Clima Tropical
7.
J Environ Manage ; 289: 112486, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33831757

RESUMEN

Climate change is a global issue threatening agricultural production and human survival. However, agriculture sector is a major source of global greenhouse gases (GHGs), especially CH4 and N2O. Crop residue returning (RR) is an efficient practice to sequestrate soil carbon and increase crop yields. However, the efficiency of RR to mitigate climate change and maintain food security will be affected by the response of GHG emissions at both per area-scale and per yield-scale. Therefore, a national meta-analysis was conducted using 309 comparisons from 44 publications to assess the responses of GHG emissions to RR in China's croplands. The results indicated that little response of GWP to RR was observed with conditions under lower nitrogen fertilizer input rates (0-120 kg ha-1), mulch retention, returning one time in double cropping systems, returning with half residue, weakly acidic soil (pH 5.5-6.5), initial SOC contents >20 g kg-1, or mean annual precipitation <1000 mm. In order to mitigate climate change and sustain food security, RR combined with paddy-upland rotation, nitrogen fertilizer input rates of 240-360 kg ha-1, and neutral soil (pH 6.5-7.5) could decrease GWP at per unit of crop yield, which ultimately leads to a lower effect on GHGI and a higher crop production efficiency. In-depth studies should be conducted in the future to explore the interactions between various factors influencing GHG emissions under RR conditions. Overall, optimizing the interactions with management and site-specific conditions, potential for regulating GHGs emissions of RR can be enhanced.


Asunto(s)
Gases de Efecto Invernadero , Oryza , Agricultura , China , Productos Agrícolas , Calentamiento Global , Efecto Invernadero , Gases de Efecto Invernadero/análisis , Humanos , Metano/análisis , Óxido Nitroso/análisis , Suelo
8.
J Environ Manage ; 289: 112526, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33848879

RESUMEN

Methane (CH4) is a prominent Greenhouse Gas (GHG) and its global atmospheric concentration has increased significantly since the year 2007. Anthropogenic CH4 emissions are projected to be 9390 million metric tonnes by 2020. Here, we present the long-term changes in atmospheric methane over India and suggest possible alternatives to reduce soil emissions from paddy fields. The increase in atmospheric CH4 concentrations from 2009 to 2020 in India is significant, about 0.0765 ppm/decade. The Indo-Gangetic Plains, Peninsular India and Central India show about 0.075, 0.076 and 0.074 ppm/decade, respectively, in 2009-2020. Seasonal variations in CH4 emissions depend mostly on agricultural activities and meteorology, and contribution during the agricultural intensive period of Kharif-Rabi (i.e., June-December) is substantial in this regard. The primary reason for agricultural soil emissions is the application of chemical fertilizers to improve crop yield. However, for rice farming, soil amendments involving stable forms of carbon can reduce GHG emissions and improve soil carbon status. High crop production in pot culture experiment resulted in lower potential yield-scaled GHG emissions in rice with biochar supplement. The human impact of global warming induced by agricultural activities could be reduced by using biochar as a natural solution.


Asunto(s)
Gases de Efecto Invernadero , Oryza , Agricultura , Fertilizantes/análisis , Calentamiento Global , Gases de Efecto Invernadero/análisis , Humanos , India , Metano/análisis , Óxido Nitroso/análisis , Suelo
9.
J Environ Manage ; 289: 112551, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33865025

RESUMEN

Life cycle assessment and kinetic modeling were used to elucidate the impact of thermal intensification (TI) on resource consumption and the techno-economic feasibility of a Fenton process at laboratory scale. Increasing temperature from 25 to 55 °C lowers treatment time (96.5%) and electricity use (67.8%) due to the positive impact of temperature on the reaction rate; however, beyond 50 °C no significant diminution in energy use, emissions, and operating cost was observed. The environmental footprint of the process is linked with energy use, operating pH, and the electricity share of the country; nevertheless, the impact of transport and infrastructure materials was lower. At 55 °C and pH of 2.8, emissions of precursors of freshwater and marine eutrophication, particulate matter formation, and ionizing radiation were reduced more than half; besides, in most of the midpoint categories, pondered by the ReCiPe-2016 method, emissions were lowered ca. 43.3%. The endpoint categories human health, ecosystem quality, and resource availability had a significant decline in disability-adjusted life years (46.0%), time-integrated species loss (42.0%), and surplus cost (33.1%). Harnessing the energy present in the wastewater itself decreased 41.9% global warming potential (GWP), but the use of steam for heating raised it 718.8%. In countries where electricity generation is dependent on fossil fuels, GWP could increase (2.0-20.0%) whereas GWP would decrease (8.8-9.4%) when renewable energy sources dominate. Operating at 55 °C and pH of 5.5 rose the reaction time (1835.5%), GWP (29.3%), particulate matter formation (44.3%), terrestrial acidification (21.8%), marine (48.9%), and freshwater eutrophication (66.7%). TI of Fenton processes could increase their treatment capacity with a small reduction in the quality of the effluent; furthermore, they can be made affordable for low-to-medium scale industries in emerging economies due to decreased resources consumption and emissions, leading to a lower treatment cost (US$0.49/m3).


Asunto(s)
Ecosistema , Combustibles Fósiles , Eutrofización , Calentamiento Global , Humanos , Aguas Residuales
10.
J Insect Sci ; 21(2)2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33822125

RESUMEN

Since its invasion into China in 1979, the fall webworm, Hyphantria cunea Drury, has spread from Dandong city (about 40°N) in Liaoning Province to Nanjing city (about 32°N) in Jiangsu Province, and to other areas. Owing to geographic and latitudinal gradients in temperature, H. cunea will encounter temperature changes during the spreading process. In this study, we verified the hypothesis that autumn warming accelerates the energy consumption of H. cunea diapause pupae. We found that, after autumn warming, the body size and mass of diapause pupae decreased significantly and raised constant temperature accelerated carbohydrate and protein consumption in female pupae, while fluctuating temperature changes had a more pronounced effect on carbohydrate and protein consumption in male pupae. Contrary to expectations, the lipid content of diapause pupae did not decrease after autumn warming, and even increased significantly. We conclude that warming in autumn accelerates energy consumption by diapause pupae, and the autumn energy consumption of diapause pupae is dominated by carbohydrates, supplemented by protein when carbohydrates are overconsumed, while lipid use is dominated by anabolic metabolism during autumn.


Asunto(s)
Metabolismo Energético , Calentamiento Global , Mariposas Nocturnas/metabolismo , Pupa/metabolismo , Animales , Metabolismo de los Hidratos de Carbono , China , Cambio Climático , Diapausa de Insecto , Metabolismo de los Lípidos , Estaciones del Año , Temperatura
11.
Nat Commun ; 12(1): 2358, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33883554

RESUMEN

Global warming has driven a loss of dissolved oxygen in the ocean in recent decades. We demonstrate the potential for an additional anthropogenic driver of deoxygenation, in which zooplankton consumption of microplastic reduces the grazing on primary producers. In regions where primary production is not limited by macronutrient availability, the reduction of grazing pressure on primary producers causes export production to increase. Consequently, organic particle remineralisation in these regions increases. Employing a comprehensive Earth system model of intermediate complexity, we estimate this additional remineralisation could decrease water column oxygen inventory by as much as 10% in the North Pacific and accelerate global oxygen inventory loss by an extra 0.2-0.5% relative to 1960 values by the year 2020. Although significant uncertainty accompanies these estimates, the potential for physical pollution to have a globally significant biogeochemical signal that exacerbates the consequences of climate warming is a novel feedback not yet considered in climate research.


Asunto(s)
Calentamiento Global , Microplásticos/toxicidad , Modelos Biológicos , Oxígeno/análisis , Agua de Mar/análisis , Contaminantes Químicos del Agua/toxicidad , Zooplancton/efectos de los fármacos , Zooplancton/fisiología , Animales , Simulación por Computador , Ecosistema , Microplásticos/farmacocinética , Océanos y Mares , Contaminantes Químicos del Agua/farmacocinética
12.
Nat Commun ; 12(1): 1512, 2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33686076

RESUMEN

Bioenergy with carbon capture and storage (BECCS) is considered an important negative emissions (NEs) technology, but might involve substantial irrigation on biomass plantations. Potential water stress resulting from the additional withdrawals warrants evaluation against the avoided climate change impact. Here we quantitatively assess potential side effects of BECCS with respect to water stress by disentangling the associated drivers (irrigated biomass plantations, climate, land use patterns) using comprehensive global model simulations. By considering a widespread use of irrigated biomass plantations, global warming by the end of the 21st century could be limited to 1.5 °C compared to a climate change scenario with 3 °C. However, our results suggest that both the global area and population living under severe water stress in the BECCS scenario would double compared to today and even exceed the impact of climate change. Such side effects of achieving substantial NEs would come as an extra pressure in an already water-stressed world and could only be avoided if sustainable water management were implemented globally.


Asunto(s)
Biomasa , Cambio Climático , Deshidratación , Carbono , Simulación por Computador , Calentamiento Global , Humanos , Plantas , Agua
13.
Nat Commun ; 12(1): 1601, 2021 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-33707454

RESUMEN

The accelerating loss of tropical forests in the 21st century has eliminated cooling services provided by trees in low latitude countries. Cooling services can protect rural communities and outdoor workers with little adaptive capacity from adverse heat exposure, which is expected to increase with climate change. Yet little is still known about whether cooling services can mitigate negative impacts of heat on labor productivity among rural outdoor workers. Through a field experiment in Indonesia, we show that worker productivity was 8.22% lower in deforested relative to forested settings, where wet bulb globe temperatures were, on average, 2.84 °C higher in deforested settings. We demonstrate that productivity losses are driven by behavioral adaptations in the form of increased number of work breaks, and provide evidence that suggests breaks are in part driven by awareness of heat effects on work. Our results indicate that the cooling services from forests have the potential for increasing resilience and adaptive capacity to local warming.


Asunto(s)
Conservación de los Recursos Naturales , Eficiencia , Empleo , Calor/efectos adversos , Clima Tropical/efectos adversos , Bosques , Calentamiento Global , Humanos , Indonesia , Árboles
15.
Nat Commun ; 12(1): 1701, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33723261

RESUMEN

Climate change poses a significant threat to global biodiversity, but freshwater fishes have been largely ignored in climate change assessments. Here, we assess threats of future flow and water temperature extremes to ~11,500 riverine fish species. In a 3.2 °C warmer world (no further emission cuts after current governments' pledges for 2030), 36% of the species have over half of their present-day geographic range exposed to climatic extremes beyond current levels. Threats are largest in tropical and sub-arid regions and increases in maximum water temperature are more threatening than changes in flow extremes. In comparison, 9% of the species are projected to have more than half of their present-day geographic range threatened in a 2 °C warmer world, which further reduces to 4% of the species if warming is limited to 1.5 °C. Our results highlight the need to intensify (inter)national commitments to limit global warming if freshwater biodiversity is to be safeguarded.


Asunto(s)
Peces , Agua Dulce , Calentamiento Global , Animales , Biodiversidad , Cambio Climático , Calor , Modelos Biológicos , Filogenia , Especificidad de la Especie , Temperatura
16.
Environ Pollut ; 276: 116696, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33744496

RESUMEN

It is a common practice to maintain soil fertility based on the paddy-upland rotation with green manure in the subtropical region of China. However, rare studies are known about greenhouse gas (GHG) emissions from the paddy-upland rotation with green manure incorporation. Therefore, we conducted a field experiment of two years to compared with the effect of two kinds of green manure (CV: Chinese milk vetch and OR: Oilseed rape), and two kinds of cropping system (DR: double rice system and PR: paddy-upland rotation) on greenhouse gases emissions. We have found that the annual accumulation of CH4 of Chinese milk vetch-rice-sweet potato || soybean was significantly reduced by 32.95%∼63.22% compared with other treatments, mainly because Chinese milk vetch reduced the abundance of methanogens by reducing soil C/N ratio. Meanwhile increasing soil permeability resulting from paddy-upland rotation also reduced soil CH4 emission. However, The annual accumulation of N2O of Chinese milk vetch-rice-sweet potato || soybean was increased by 17.39%∼870.11% compared with other treatments, mainly attributed to paddy-upland rotation decreased soil pH and nosZ abundance and increased nirK and nirS, thus enhancing N2O emission, meanwhile the Chinese milk vetch incorporation and its interaction with the paddy-upland rotation has greatly enhanced the contents of NO3--N and abundance of ammonia-oxidizing archaea (AOA). The area-scaled global warming potential (GWP) and the biomass-scaled greenhouse gas emissions intensity (GHGI) of Chinese milk vetch-rice-sweet potato || soybean was reduced by 19.01%∼50.69% and 5.38%∼35.77% respectively. Thereby, the Chinese milk vetch-rice-sweet potato || soybean cropping system was suitable for agricultural sustainable development.


Asunto(s)
Astrágalo (Planta) , Gases de Efecto Invernadero , Oryza , Agricultura , China , Calentamiento Global , Metano/análisis , Óxido Nitroso/análisis , Rotación , Suelo
17.
Nature ; 592(7852): 76-79, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33647927

RESUMEN

In ecosystems, the efficiency of energy transfer from resources to consumers determines the biomass structure of food webs. As a general rule, about 10% of the energy produced in one trophic level makes it up to the next1-3. Recent theory suggests that this energy transfer could be further constrained if rising temperatures increase metabolic growth costs4, although experimental confirmation in whole ecosystems is lacking. Here we quantify nitrogen transfer efficiency-a proxy for overall energy transfer-in freshwater plankton in artificial ponds that have been exposed to seven years of experimental warming. We provide direct experimental evidence that, relative to ambient conditions, 4 °C of warming can decrease trophic transfer efficiency by up to 56%. In addition, the biomass of both phytoplankton and zooplankton was lower in the warmed ponds, which indicates major shifts in energy uptake, transformation and transfer5,6. These findings reconcile observed warming-driven changes in individual-level growth costs and in carbon-use efficiency across diverse taxa4,7-10 with increases in the ratio of total respiration to gross primary production at the ecosystem level11-13. Our results imply that an increasing proportion of the carbon fixed by photosynthesis will be lost to the atmosphere as the planet warms, impairing energy flux through food chains, which will have negative implications for larger consumers and for the functioning of entire ecosystems.


Asunto(s)
Biomasa , Cadena Alimentaria , Agua Dulce , Calentamiento Global , Nitrógeno/metabolismo , Plancton/crecimiento & desarrollo , Plancton/metabolismo , Carbono/metabolismo , Ciclo del Carbono , Lagos , Fotosíntesis , Factores de Tiempo
18.
mBio ; 12(2)2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33727350

RESUMEN

Global warming was proposed to be a contributing cause for the nearly simultaneous emergence of different clades of Candida auris as a nosocomial pathogen in different continents. The global warming emergence hypothesis posits that C. auris existed in the environment prior to its clinical recognition and became pathogenic for humans because of thermal adaptation in response to climate change. The isolation of C. auris from two sites in the remote Andaman Islands establishes it as an environmental organism, a necessary condition for the hypothesis. The observation that one environmental isolate grew slower at mammalian temperatures than clinical strains is consistent with the notion that their ancestor recently adapted to higher temperatures. The knowledge that C. auris can be recovered from the environment should prompt additional searches to define its ecological niches, and the analysis of future environmental isolates will provide evidence for validating or refuting the global warming emergence hypothesis.


Asunto(s)
Candida , Candidiasis , Animales , Candida/genética , Calentamiento Global , Humanos , India , Islas , Humedales
19.
Sci Total Environ ; 771: 145167, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33736151

RESUMEN

Ocean acidification and warming are recognized as two major anthropogenic perturbations of the modern ocean. However, little is known about the adaptive response of phytoplankton to them. Here we examine the adaptation of a marine diatom Thalassiosira weissflogii to ocean acidification in combination with ocean warming. Our results show that ocean warming have a greater effect than acidification on the growth of T. weissflogii over the long-term selection experiment (~380 generations), as well as many temperature response traits (e.g., optimum temperatures for photosynthesis, maximal net photosynthetic oxygen evolution rates, activation energy) in thermal reaction norm. These results suggest that ocean warming is the main driver for the evolution of the marine diatom T. weissflogii, rather than oceanacidification. However, the evolution resulting from warming can be constrained by ocean acidification, where ocean warming did not impose any effects at high CO2 level. Furthermore, adaptations to ocean warming alone or to the combination of ocean acidification and warming come with trade-offs by inhibiting photochemical performances. The constrains and trade-offs associated with the adaptation to ocean acidification and warming demonstrated in this study, should be considered for parameterizing evolutionary responses in eco-evolutionary models of phytoplankton dynamics in a future ocean.


Asunto(s)
Diatomeas , Aclimatación , Calentamiento Global , Concentración de Iones de Hidrógeno , Océanos y Mares , Agua de Mar
20.
Science ; 371(6533): 1042-1045, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33674492

RESUMEN

Uncertainty remains regarding the role of anthropogenic climate change in declining insect populations, partly because our understanding of biotic response to climate is often complicated by habitat loss and degradation among other compounding stressors. We addressed this challenge by integrating expert and community scientist datasets that include decades of monitoring across more than 70 locations spanning the western United States. We found a 1.6% annual reduction in the number of individual butterflies observed over the past four decades, associated in particular with warming during fall months. The pervasive declines that we report advance our understanding of climate change impacts and suggest that a new approach is needed for butterfly conservation in the region, focused on suites of species with shared habitat or host associations.


Asunto(s)
Mariposas Diurnas , Extinción Biológica , Calentamiento Global , Animales , Conservación de los Recursos Naturales , Ecosistema , Densidad de Población , Estaciones del Año , Estados Unidos
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